Hold-in electromagnet valve



March 26, 1935. E. G. PARVIN HOLD-IN ELECTROMAGNET VALVE Filed April 9, 1932 v mlull+lll III I INVENTOR- R M ATTORNEYJ Patented Mar. 26, 1935 P ATENT OFFICE 7 HOLD-IN ELECTROMAGNET VALVE Edward G. Parvin, Roselle, N. .L, assignor to National Pneumatic Company, New York, N. Y., a corporation of West Virginia Application April 9, 1932; Serial No. 604,215

2 Claims.

ated by an electrical impulse and which will stay in operated-position until given another electrical impulse to return it. to normal position.

The-invention.involvesan electromagnet having two windings associated with a steel yoke and armature of a construction so that when one of the windings is-energized the valve is operated and remains operated until the other winding is energized, both of which energizations occur momentarily.

These and manyother objects, as will appear from. the following disclosure, are secured by means of thisinvention.

This. invention resides substantially in the combination, construction. arrangement, and relative location of parts, all as will be described in detail in the following specification.

Referring to. the drawing Figure 1 is an elevational view, partly diagrammatic and partly a vertical cross-sectional View of the device of this invention; and

Fig. 2- is atop planview thereof. 1

Intheoperation-of pneumatic motors through controlby meansof; electromagnet valves it is necessary to provide several electromagnet valves to effect-.movement of the engine in both directions; and in some. forms of apparatus it is necessary. to employ in connection therewith an additional rotary valve operated by pistons. For example, in the operation of a differential fluid.

. pressure engine-two electromagnet valves-and a pistonoperated rotary valve are necessary in order to. effect full control: of the engine for ,movement in both directions. c

Thei rgeneralrobject of :this invention is to provide a much simplified valve of a type which remains operated upon impulse energizations and which returns to normal upon another momentary energization. With such a valve it is possible to control a differential fluid pressure engine without any additional apparatus and with but one valve.

To understand the nature of the invention reference will now be made to the drawing. The device is shown comprising an L-shaped yoke 1, of magnetic material having an upstanding portion which terminates in a pole piece 2. Mounted on the yoke is a soft iron core 3 upon which is mounted a winding comprising the portions 4 and 5. Pivotally mounted on a non-magnetic standard 6 secured to the yoke is an armature '7.

The yoke and armature are preferably madeof hardened magnetic steel so that when magnetized by means of the winding they will retain considerable residual magnetism. The core 3 provided with a central hole passing therethrough in alignment with a hole in the yoke, as is disclosed in Fig. 1. A vertically'slidable rod is mounted in this hole and projects a short distance above the top of the armature, as shown: Secured to the armature by means of an anchor piece 8 and screws is a flat spring 9 which rests upon the upper end of the rod 10; The rod projects through the hole in the yoke into valve casing 11 which has a central passage therethrough closed by means of a screw plug 12.

Within the central passage is'a plug 13 having a hole therethrough and aseat on-its upper surface which cooperates with the conical end of the rod 10 serving as a valve, as indicated'at 19:

Situated between theplug 13 and'the screw plug 12 is another plug 14 which has a passage there through and a seat on the bottom portion thereof cooperating with the valve which'isconnected to the rod 10, as shown. A coiled spring 18-norma1ly holds the valve 20 onits seat and :the valve 19 off its seat. The space above the plug 13 is open to the atmosphere through the exhaust passage 15. The space between the plugs 13=and 14 is connected through a passage 16 to the piston of the engine to be operated, or to any other device M to be supplied with fluid pressure.

At His a passage openinginto the casing 11 below the plug 14, as is clear from the drawing. The passage 17 is supplied with fluidpressure from a suitable source and is alwaysdirectly connected thereto. I

The portion 4 of the winding is connectedeat one terminal by wire 22 to one contact of a push button switch 23. The. other terminal of the. winding 4 is grounded by means of a lead 21 common with one terminal of the winding 5. The other terminal of winding 5 is connected by wire 2'7 to one contact of a push button switch 28. A common wire 24 connects the other contacts of the switches 23 and 28 to one terminal of a suitable current source 25, which has its other terminal grounded. The particular form of valve shown in the drawing is known as the pressure type. It is obvious, however, that any suitable form of valve may be operated by means of this mechanism.

When the device is connected to a door engine, for example, and push button switch 23 is momentarily closed winding 4 is energized. As a result armature 7 is attracted by the core and moves down until its free end approaches or engages the pole piece 2. The armature and pole piece being made of hardened magnetic steel the armature will remain in position in close proximity to or in contact with the pole piece because of the residual magnetism in the parts. The only force tending to move the armature back to normal position is that exerted by spring 18 which is now under compression. The downward movement of the armature '7 will cause rod 10 to move downwardly so that valve 20 unseats and valve 19 seats. The force exerted by spring 9 is greater than that exerted by spring 18 so that there is no relative movement between the rod 10 and the armature 7. Hence the valve will remain in operated position and fluid pressure will flow from the source through passage 17, through the passage in the plug 14, and out through passage 16 to the device to be operated.

To cut off the supply of fluid pressure it is only necessary to momentarily close push button switch 28 with the result that winding 5 is energized and creates an opposing flux through the iron parts which neutralizes the residual magnetism thereof and permits spring 18 to close valve 20 and open valve 19 and return armature '7 to the position shown in the drawing, which is the normal position. Fluid pressure will then exhaust from the device through passage 16 through the passage of plug 13 and to the atmosphere through the exhaust ports 15.

It is, of course, apparent that winding 5 will be so proportioned in ampere turns that it will generate just sufficient magnetic flux to neutralize the residual magnetism of the parts. Although the portions 4 and 5 of the windings have been shown as distributed in alignment, it is of course apparent that one may be wound over the other without departure from the invention.

The spring 9 is provided so as to take care of any wear on the valve parts and to insure that valve 20 may always seat under the action of spring 18.

From the above description it will be apparent that this invention resides in certain principles of construction and operation which may be embodied in other physical forms without departure therefrom. I do not, therefore, desire to be strictly limited to the disclosure as given for purposes of illustration but rather to the scope of the appended claims.

What I seek to secure by United States Letters Patent is:

1. In an electro-magnetic valve device, a magnetizable yoke member having an upstanding portion terminating in a pole piece, a standard mounted on said yoke member and spaced apart from said upstanding portion, a soft iron core mounted on said yoke member and disposed between said standard and upstanding portion, a coil mounted on said core and having a twopart winding, an armature hinged at one end to said standard and cooperating at its opposite end with said pole piece in combination with a valve casing having passages communicating, respectively, with a source of pressure supply, the engine or other device to be controlled, and, with the outer air, said passages having bored closures to separate them from each other, a rod extending longitudinally through said core and into said valve casing, said rod having an extension passing through said bored closures, said rod and its extension formed into oppositely seating valves respectively cooperating with seats formed in said closures, resilient means engaging the respective ends of the rod in opposite directions to hold the same against endwise movement with relation to the armature, one of said resilient means being mounted on said armature and independent circuit closure devices for the respective circuits of the parts of said winding, whereby currents in opposite directions may be supplied momentarily to said respective parts of the windings.

2. In an electro-magnetic valve device, a yoke member of magnetic material having an upstanding portion terminating in a pole piece, a non-magnetic standard mounted on said yoke member and spaced apart from said upstanding portion, a soft iron core mounted on said yoke member and disposed between said standard and upstanding portion, and having a bore longitudinally therethrough, a coil on said core having a two-part winding applied in reverse directions with respect to each other, an armature for said coil hinged at one end to said standard and cooperating at its opposite end with said pole piece, and a spring member mounted upon said armature in combination with a valve casing having passages communicating respectively with a source of pressure supply, the engine or other device to be controlled, and with the outer air, bored closures to separate said passages from each other, a rod extending longitudinally through the bore of said core and into said valve casing, said rod having an extension arranged to pass through the bores of said closures, said rod and its extension formed into oppositely presenting valves, said closures having seats with which said valves respectively cooperate, a spring arranged in said valve casing and acting to press the valve on said extension into its seat and to unseat the valve on said rod, the other end of said rod arranged to be engaged by the spring member on said armature and independent closure means for the respective circuits of said winding parts.

EDWARD G. PARVIN. 

